This invention relates to machine control apparatus and, more particularly, to apparatus for stopping the feed of stock to a machine when the end of the stock is sensed.
One step in the production of automobile carburetors involves the manufacturing of fuel metering rods which are installed in a fuel bowl of the carburetor to control fuel flow. A machine for manufacturing fuel metering rods typically employs a coil of stock which is fed first to a straightening unit so minor variations in the stock can be corrected. After straightening, the stock is fed to a forming unit containing a series of tools which neck down the stock at appropriate sections to form the fuel metering rod. After this forming step has been accomplished, the resultant fuel metering rod is severed from the remainder of the stock and each rod is collected in a bin from which it is taken to a carburetor assembly line.
One problem encountered with such machines involves damage to the forming tools when the end of a coil of stock is not sensed or observed in time for the operator of the machine to stop the machine so the end of the coil is fed into the straightening unit. When this occurs, a reciprocal carriage within the straightening unit may force the end of the stock forward and, in so doing, damage the forming tools. As a consequence, the forming tools have to be replaced, which is not only costly, but adds to equipment-down time and may disrupt assembly line operations. Machines of the type described may come equipped with an electrical stop device, however, such devices are expensive.